Reversible room temperature ammonia sensor based on the synthesized MoS2/PANI nanocomposites

Abstract

Successful fabrication and optimization of molybdenum disulfide (MoS2)/polyaniline (PANI) nanocomposite-based room temperature ammonia sensors have been reported in this work. The hydrothermal technique was used to synthesize nanocomposites of MoS2 and PANI at different amounts of PANI. For this, the precursor values were changed by choosing three different values of 0.65 (MP1), 1.1 (MP2), and 2.2 (MP3) for the ammonium heptamolybdate/PANI weight ratio. Successful fabrication of nanocomposites was confirmed by Raman analysis and x-ray diffraction. According to FESEM images, MoS2/PANI nanocomposites have been composed of 1D-PANI nanofibers covered by 2D-MoS2 nanosheets and created a porous morphology that influenced their sensing characteristics significantly. The samples’ ability to detect ammonia at room temperature was examined by fabricating sensor devices using the synthesized MoS2, PANI, and nanocomposites. The fabricated sensor using MP2 showed much better gas-sensing properties than other samples. This sensor showed about 4.6 and 1.6 times higher response than pristine PANI and MoS2 sensors for 10 ppm of ammonia, respectively, with better selectivity toward ammonia than other gas species. This research shows that compositing PANI with MoS2 significantly improves the gas detection performance of MoS2.